1. Field of the Invention
The present invention relates to a method for the application of a viscous liquid, such as an adhesive or sealant, to floor and wall surfaces.
2. Description of the Prior Art
When installing carpet it is the usual practice to utilize an adhesive to attach the carpet to the surface of the floor or the wall. Hand troweling is the predominant method for applying adhesives to such surfaces. However, troweling is labor intensive, slow and ergonomically undesirable, and for these reasons is seen as economically disadvantageous.
Included in the prior art is a system for spray application of a liquid adhesive to floor and wall surfaces known as the Roberts Monobond.RTM. Spray Adhesive System. FIG. 1 is a highly stylized diagrammatic illustration of the Roberts Monobond.RTM. Spray Adhesive System. Such a system includes a high pressure pump P that pumps an adhesive V from a reservoir R, through a flexible hose F, and from a spray wand apparatus generally indicated by character W. Typically the adhesive is a solvent-based adhesive. The pressure of the adhesive is controlled by a pump pressure governor diagrammatically indicated by the reference character G. The spray wand W includes a trigger handle H connected through an extension barrel B to a spray tip T. A system such as that shown in FIG. 1 is believed to have associated with it a number of disadvantages.
Adhesive applied by the known spray system has a tendency to splash, making precision lay-down difficult. By "splashing" it is meant the undesired application of liquid to any nearby surface other than the intended surface, including adjacent wall or floor surfaces, clothing and feet of the operator, etc. Splashing is caused by the rebounding of larger sized droplets upon impact with the surface and is especially disadvantageous in regions of a floor close to a wall surface or adjacent to an existing carpeted area.
Also, the known system generates a high degree of mist. Misting is believed to be disadvantageous for a variety of reasons. Misting causes overspray which is a fringe-like deposition of liquid in a region immediately surrounding the area of desired application. The inhalation of mist is harmful to an operator and requires the use of respirator equipment. Misting often results in an adhesive coating on walls, furnishings and clothing, thus necessitating protective covers. Solvent-based adhesive, the most common adhesive used, emits volatile organic compounds. Thus, it is often necessary to vacate the area of the building during adhesive lay-down. Clean-up of solvent-based adhesive is also difficult, requiring the pumping of large volumes of solvent through the spray system in order to flush the adhesive from the equipment.
The known spray system is believed to have ergonomic problems as well. The system is usually configured so that in order to effect perpendicular-to-the-floor spraying (to minimize splashing) the operator is required to flex the wrist of the arm holding the handle at an uncomfortable angle. Moreover, in order to bring the tip within a reasonably close distance from the surface the operator is required to stoop at the waist. These postures are ergonomically stressful to the operator. The known system also has the disadvantage in use that it frequently results in spraying the tops of the feet of the operator.
In view of the foregoing, it is believed advantageous to provide a method and system for the application of a viscous liquids such as an adhesive or sealant to a surface which overcome the above disadvantages.